High-volume products such as tablet computers, mobile devices, and motor vehicles typically include at least one camera. The camera includes an image sensor that is manufactured, with hundreds of additional identical image sensors, on a single image-sensor wafer via a wafer-level manufacturing process. Some image-sensor wafers include a transparent layer, such as a cover glass, for protecting each image sensor. The transparent layer has a thin-film optical filter thereon that allows a predetermined wavelength range to be transmitted through the transparent layer to one of the image sensors. The thin-film optical filter tends to warp the transparent layer and, upon singulating the image-sensor wafer to yield image sensor dies, also delaminate from the transparent layer.